Answer:
Step-by-step explanation:
Variance is the sum of squares of all items x from mean. i.e
Variance =
Being the sum of squares variance can never be negative irrespective of mean being negative.
Std deviation is the square root of variances. This will thus be less than variance if variance >1 other wise std deviation will be bigger than variance.
Hence option d is right.
Answer:
0.0159
Step-by-step explanation:
Given that a common practice of airline companies is to sell more tickets for a particular flight than there are seats on the plane, because customers who buy tickets do not always show up for the flight.
Here if X is the no of persons that do not show up, then X is binomial as each trial is independent with p = 0.04 and n =150 (no of tickets sold)
The plane is overbooked if more than 150 show up
i.e. less than 2 do not show up
Hence the probability that the airline overbooked this flight
=